The Siege of the Worlds
by M.J. Joyce-Crowling
Summary: They thought that their relationship shattering to pieces was bad enough. But when Cipher transported them to a dimension where a secret society is crumbling to the Dark Side, it's up to Dipper and Mabel to save both worlds, and learn the value of love and family from a pair of twins who've lost everything: their alternate selves. Set during HP7, at Hogwarts, after DMVSTF.


AN: HAAAAAYYYYOOO! *waves* *chuckles nervously*

So... yeah, welcome to this madness! My obsession with Gravity Falls, Harry Potter, plus probably angst and pain (I mean, isn't it hilarious?! *winks*) made me think, hey, why not a crossover? Last time I checked there were only twelve fanfics about these two merging together. I guess I'm the thirteenth (cool, the twins are turning 13 too!), and I hope I'd do this justice, just like those AMAZING writers. Hope you like, and review! Anyways, onwards Aoshima, to the story!*screams like a lunatic.*

Disclaimer: Gravity Falls and Harry Potter do NOT belong to me, because if it did, the world would already have ended. (Voldy and Bill! Wew!)

Oh, so that your mind won't be boggled, this part is in the point-of-view of the Dipper and Mabel from the Hogwarts dimension. They're called as Dip and Bel there, just to avoid confusion. Alright, let's begin!

* * *

 _Prologue_

 _These are dark times..._

The boy, who was not older than fourteen years old, bit his lip and clenched his fists, trying to control the whirlwind of emotions inside him, which was creating havoc and confusion. He glanced at his sister, who had already broken down into tears, wringing her hands in despair.

" Do you have to go?" she whispered, rushing towards two grown ups who looked like they're their parents, and hugging them tightly. " Mom, Dad, let us come with you..."

The boy nodded, his brown eyes overbright, as the cold gusts of wind whipped his hazel hair. _Any time now..._

"Y-you c-can't, dear," her mom stammered, trying to hold back her own tears as she engulfed Mabel in her arms. "Y-you m-must stay at H-Hogwarts... you and D-Dip... it's safer-"

"No, it isn't!" he finally yelled furiously. All of this isn't fair. _It isn't fair_. "Mum, Snape's headmaster, the Carrows are there, and so are the dementors! _Anywhere_ is safer but Hogwarts! "

His father bent down and looked at his son straight in the eye, placing a hand on his shoulder.

"Dip, you know what the situation is," he muttered. "We need to go into hiding. I can't let them take your mom-"

"We don't want to either-!"

"I know," his father cut him off. He hesitated, then carried on. "Dip, things change... they might never be the same again..." He shook his head. "We... we might never see you... again..."

"Don't say that!" Dip said fiercely, his heart plunging down. There was a burning feeling in his chest, and it was now in the corner of his eyes, too. "We _will_ see you... You, Mom, Bel and I...we should... we...we..."

His voice cracked and died.

His father took a deep breath. "The Ministry has considered me a Blood traitor, and they want me as badly as they want your mother, as they want Muggleborns.

" But, not you," he continued, as Dipper showed every sign of interrupting. "Both of you are half-bloods... you would do fine... you have your futures ahead of you... You need to stay at Hogwarts... just... promise me... one thing..."

There were two loud CRACKS and the sounds of shattering glass and banging furniures from the first floor of their house broke the stillness of their neighborhood.

" Search for 'em," yelled a rough voice. " Don't let those two escape!"

Mabel turned to their mother fearfully, who was now faint with terror. His father gripped hard on his arm.

"Protect your sister," he whispered hurriedly, "protect each other-"

"I HEAR PEOPLE UPSTAIRS!" another rough voice bellowed. " GET THEM!"

" You'll understand one day, " he whispered, as heavy footsteps pounded on the stairs.

He let go of his son, grabbed his wife, and with a small _pop_ , disappeared to nowhere.

Dipper stared at the spot where his parents Dissapparated, an odd buzzing in his ears.

 _Protect your sister... protect each other..._

His hand suddenly enclosed upon hers, and, squeezing it tightly, he veered themselves to face the door, where the footsteps and shouts were getting louder and louder. She was breathing heavily, still sobbing, and he instantly stepped up in front of her, shielding her from harm.

The door burst open with a CRASH, and Mabel gave a shuddering gasp.

But as the Ministry officials roared with fury when they realized that their prey was gone, Dip knew one thing. No matter what this war brings to them, he knew it with all his heart.

 _I'll protect you, Bel. I'll protect you._

She returned the pressure on his hand, as the officials who were sent to take their parents away started towards them.

 _Whatever it takes._

* * *

AN: Well, at least two of them got their priorities right. XD I... hang on... did I just leave those two in the hands of Death Eaters?! *pause*

Meh, they're Dipper and Mabel. They can handle it.


End file.
